The Stability Analysis Of The Drill Construction Platform

With the flourishing development of the economy in our country, many cross-river and cross-sea bridges are built in many places. Due to the longer span of the bridges and the emergence of new types of bridges, more attention has been paid to the construction control technology in engineering community. Undoubtedly, the foundation is one of the most important parts of the bridge architecture. It is impossible to guarantee the stability of the architecture without well-grounded foundation. So, the quality of the foundation directly affects the reliability of the structure, and construction platform is the prelude of the large architecture's foundation construction.The couplings-among-piles are the components which are used to enhance couples among below piles and increase stability. The form, stiffness and positions setting of the coupling-during-piles have direct effect on the stability of the construction platform. This paper expatiates relevant basic theories before the analysis the entity model. Firstly, it introduces the present situation of the researches into the construction platform system of depth pier at home and abroad, and narrates its characteristic. Secondly, this paper discusses two kinds of problems on stability in detail and probes into their FEM solution methods. Thirdly, this paper introduces wave theories with the emphasis on the linear wave theory, Stokes three-order wave theory and Morison theory.Many calculation models are adopted in this research in order to get a clear picture of the factors that affect the stability of the construction platform. Firstly, three structure models are projected on the basis of the position of the couplings-among-piles of the platform. Secondly, six work conditions are planned according to the arrangement of the cranes. At last, the effect of the wave load on the platform is calculated in two ways. Through software ANSYS, thirty-six calculation models are set up, their stable coefficients are calculated and three groups of curves that describe the relationship of the stable coefficient and the underwater depth of the couplings-among-piles are drawn. On the basis of the above-mentioned curves, the following conclusion can be drawn: the nearer the position of the couplings-among-piles is to the bottom of the piers, the bigger the stable coefficient of the construction platform is, which means that it is more stable. Of course, the lower the position of the couplings-among-piles is, the more difficult is underwater working.Calculating the stable coefficient of the construction platform is to meet the demand of the security, applicability and durability. Design and construction should be considered integratively during designing in order that they can supple and complement each other.